Since the advent of the latest chaos codex, we legion players have been able to take non-marked units without losing the special rules bestowed for being loyal to the chaos gods.

Who has?

I've seen Khorne armies feature a unit or two of 1ksons, EC armies with a plaguemarine squad and a khorne DP. I have steered clear from non-marked units (not even a popular lash-prince). All the units in my army have MoN/plaguemarines. No bikes...Raptors etc. Am I screwing myself by doing this? Probably.